Airplane wing with slotted flap, cove lip door, and spoiler



May 27, 1958 R. E. PEARsoN 2,836,380V

AIRPLANE WING WITH SLOTTED FLAP, COVE LIP DOOR, AND SPOILER Filed April 25. 1955 2 Sheets-Sheet 1v A r roe/V56' May 27, 1958 R. E. PEARsoN 2,836,380

AIRPLANE WING WITH sLoIIED FLAP, covE LIP nooR, AND SPOILER Filed April 25. 1955 2 Sheets-Sheet 2 IN VEN TOR. PA VMND PEA ESO/V BY f W-Mqaww I I Q A frog/V945' ilnited States Patent O AIRPLANE WLNG WIT H SLTTED FLAP, COVE Ll? DUUR, AND SPOILER Raymond E. Pearson, Seattle, Wash., assigner to l'oeing Airplane Company, Seattle, Wash., a corporation of Delaware Application April 25, 1955, Serial No. 503,633

11 Claims. (Cl. 244-42) The use of slotted flaps at the trailing edge of an airplane wing, for added lift and for air-braking, is common. This invention concerns such a ap, especially in a high-speed airplane, with certain accessory devices such as a cove lip door and a spoiler door, and the actuation of these doors as a result of and coordinated with movement of the tlap by its actuator, between its up position, wherein it lies in substantial continuation of the interrupted wing trailing edge contour, and a down position, wherein it is displaced rearwardly and deflected downwardly from its up position.

According to the present invention the downward pitching moment about a local center of rotation, such as is produced by' the downward deilection of the ap, is countered by the use of a spoiler door which is normally arranged to constitute a rearward continuation of the upper wing skin, but which is uptilted at its rear edge when the flap is in or as the iiap approaches its full down position, such uptilting of the spoiler, even by a few degrees, producing a torque about the local center of rotation counter to the downward pitching moment produced by the downward detlection of the ap.

Also according to this invention a cove is defined between the upper wing skin (or the spoiler door as a rearward continuation thereof) and a rearward continuation of the Vwings lower skin, such as may be constituted by a cove lip door hingedly mounted by its forward edge upon the wing; cove houses the slotted nose of the ap in the aps up position, and the upper and lower continuations of the wing skin-the spoiler door and the cove lip door, respectively-close the exit and the entrance to the flaps slot when the flap is in its up position, but are of a length such that when the flap is displaced rearwardly and detlected downwardly, the aps slot will be uncovered. in the full down position of the tiap one or both of two doors will be tilted upwardly to define a slot ahead of the flaps nose.

Because of space limitations it is preferred that the movement of the doors between the positions indicated above, in coordination with the flaps movements, be accomplished not by separate actuators, but by the flap or by mechanism carried by or engageable by the ap during the latters shifting between its up position and a down position, and in particular that a cam track carried by the flap engage a cam follower carried by the cove lip door to tilt the rear edge of the cove lip door upwardly, after a predetermined rearward movement of the flap from its up position; further, that latch means be shifted, by rearward movement of the ap, from an unlatched to a latching position, to interengage complemental latching means on the cove lip door to hold the latter uptilted after the cam track (the length whereof is limited by space limitations) disengages the cam-follower as the ap continues its downward movement; still further, that a spoiler actuator be positioned for engagement by the ap (preferably by the same means that shifts the latch means, and after such shifting) and guided for move- 2,836,380 Patented May 27, 1958 ICC ment in a definite path, so that it will tilt the spoiler door upwardly at its rear edge as the tlap approaches or reaches its full down position; nally, that the several parts are reversely actuated, positively or by yieldable resilient means, or both, and in reverse order, by return movement of the flap to its up position,

lt is not intended to imply that the spoiler is only actuatable by and during downward movement of the flap, for in the actual installation the spoiler may be tilted upwardly for air-braking independently of the flap, by an actuator independent of the flaps actuator, but this constitutes mechanism separate from this invention, and is not herein disclosed. The actuation of the spoiler in coordination with the ap, and by the aps actuator, through the mechanism of this invention, is part of the subject matter of this invention, both per se, and in conjunction with the cove lip door and the latters relationship with the flap, the latchng mechanism, etc.

The general objects of this invention, and the mechanisrn whereby such objects may be attained, are outlined above, and will be better understood from the detailed description to follow.

The drawings illustrate the invention in a typical installation.

Figure l is in general a chordwise section through the trailing edge of an airplane wing, and through a tlap associated therewith, illustrating the Hap and associated parts in the up position.

Figure 2 is a similar view showing the parts following the completion of the first phase of movement toward the down position.

Figure 3 is a similar view showing parts in the position corresponding to the completion of the second phase of the movement towards the full down position, and Figure 4 is a similar View showing parts in the full down position.

Since an airplane wing, interrupted in its trailing edge contour for the reception of a flap, is known and commonly used, it is only necessary to -show here the wing, indicated generally by the numeral 1, in its trailing edge portion, the wing including a spanwise bulkhead 16, an upper wing skin 12, and a lower wing skin 13. To the rear of the bulkhead 10 a flap indicated as a whole by the numeral 4 is of a general shape to complete the upper and lower wing skin contours, notwithstanding that it is formed with a slot 40 between its nose portion 41 and its main portion 42.

Rearwardly of the bulkhead 10 the two wing skins have rearward continuations which define between them, and rearwardly of the bulkhead, a cove i4, within which is received the nose of the flap 4. For the purposes of this invention it is preferred that these rearward continuations of the upper and lower wing skins be formed through the medium of two doors, an upper spoiler door 2 hingedly mounted at 20 along its forward edge in rearward continuation of the upper wing skin contour l2, and a lower cove lip door 3 hingedly mounted at 30 upon the wing structure, to constitute a rearward continuation of the lower wing skin tcontour 13. These two doors 2. and 3 are of such length that when the flap 4 is in its full up position the spoiler door 2 extends past and closes the exit of the slot 40 of the flap, and the cove lip door 3 extends rearwardly to the main portion 42 of the ap and closes the entrance to the slot 4t). This position of the parts is shown in Figure 1.

A lead screw 44, rotatable by power means, not shown, with respect to a nut 43 carried by the flap, or any other suitable actuator, elects movement of the flap from and back to its up position. The flap is supported and guided for movement along a track 15 mounted upon the wing structure extending rearwardly from the bulkhead 10,

and contained substantially wholly Vwithin the cove 14, along which track roll that-rack rolls 45 carried by the flap in the vicinity of its nose. The'track isgivena predetermined curvature, so related to the ap asrtol cause theap'to move, under the influence of the leadV screw 44 and nut 43, rearwardly and at the Vsame time to be delected' downwardly, as compare, for instance, Figures l, 3 and 4. This is a more or less knowncoustruction and mounting of ailap and its actuator, and by'itself is not claimed in this application. Y, Y Y

The covelip door 3, being subjected to positive pressure tending todedect it upwardly, must be positively held in all its positions. A cam Vtrack 46 is xedly held to the Vflap 4, extending forwardly from the slot entrance at ,main element 42 of the ap as far as it is feasible for it to go. A cam follower 34 is carried bythe swinging edge of the cove lip door. Because of space limitations and the shape of the cam track which would be necessary if the cam track were to remain at all times engaged with the cam` follower 34, it has been found necessary to stop the camV track short, and to elfect disengagement between the Acam track d and the cam follower 34, Vatleast in Y the ,full down position ofthe ap. Latching means 5, to

be later described, are at such time in engagement with the complementallatching pin 3 3 carried bythe cove lip door, and Vthese latching means hold the door uptilted Vas later described. t Y 'j cam track 46Qarnd the cam follower Reverting to the 34, it Yis'necessary.toiprm'lide for little or no upward Vswinging of the cove'lip door during 'the first phase of rearward shifting and downward deflection Vof Vthe yflap 4. To that endthe initial portion of the carn track 46, designated 46a, is, in the up position of theY ap, more or less of the same curvature as the ap guidetrack V15. in consequence, as may be seen by comparison; of Figures 1 and 2, until the cam follower 34 reaches the point 4612 in 'the cam track 46, there is no appreciable jupward tilting of the cove liptdoor 3.

the movement of the ap from the position of Figure 2 to that of Figure 3 the cove lip door is tilted upwardly` fairly rapidly and substantially. Eventually, however, and before the flap has reached its full down position, the end of the cam track disengages `the cam follower 34,

and the latter passes out of theV open mouth 46d of the cam track. By this time the latching means, already referred'to, have become engaged.

The latching means includes a' cove lip hook or catch 5 pivotally mounted upon Xed structure at 50, and y acted upon by an overcenter compression spring 57, tending to position the hook in the upswung or unlatched position ofpFigure l, or when moved past center, to po- Vsition the hook inthe position Vof Figure 3, ready to en- Invorder to. move it betweenv these two positions a lug 47 is carriedrby the flap at or gage the cove lip door.

ahead of its nose, in position to engage la corresponding lug 54 on .the hook 5. These two lugs are shown coming into envagement Vin Figure 2, and by a slight further movement of the ap to the right, ytowards its downV position, the latch hook 5 is thrown to and' held in its read-to-engage position, as shown in Figure 3, being stopped in that position by its blunt nose 55 engaging the end ofthe cam Vtrack 46,1 as shown'in Figure 3.

Vat 20, and being subjected at all times to downward pressure, needs no latching means Vto hold Vit down', but Vcan be pushed upwardly from within the cove at the properV time. A spoiler actuator 6 is guided upon a` cam track 16, which generally parallels the guideV track,v 1 i5, the actuator 6 being mounted by means of rollers' 6), and being urged to the left, as 'viewed in the several figures, by a kcased compression spring 61 secured to the spoiler actuator 6, and at 62 to fixed structure of the wing. The spoiler actuator `is formed also with a lug V63, positioned to be engaged by a corresponding Ylug movable with the ap, and preferably by the same lug if?. as actuates the lug 54 of the latch hook 5, after this lug 47 has moved the hook to ready-to-latch position and has passed therebeyond. The lug 47, upon engaging theY lug 63, pulls the spoiler actuator 6 rearwardly, or to the right as seen in the several views, com;- pressing the spring 61, and the parts are so shaped and arranged in conjunction with the curvature of the cam track 16 that thisrearward movement of the spoiler actuator 6 pushes upwardly on the trailing rear edge of the spoiler and detiects it upwardly to theY desired extent, in the manner shown in Figure 4.

Y It will beV observed that in the up position of the parts Y shown in Figure l the cove lip door Sand thespoiler At that point the cam. track rises rather Ysteeply in the portion 46c, so that'in door 2 constitute smooth rearward continuations of the 1 respective lower and upper wing skin contours, and close j the entrance and the exit, respectively, of the slot 4.0'

through the tiap 4. In the full down Vpositionof Figure 4, however, the cove lip door'3 is uptilted to an ap.- l preciable extent and cooperates with the spoiler door and with the nose portion 41.0f the ap to define aV further slot about the nose of the ap, which isrof lfurther assistauce in controlling the air flow kover and about the flap.

n To recapitulate, the first stage of the rearward movement ofthe` flapV 4 causes little or no change in the positions of the cove lip door 3 and the spoiler door 4. The completion-'of this first ,phase is shown in Figure 2. `The Vslot'fll) has been opened, and the flap is slightly downwardly deflected, so that the lift of the WingV is increased. During the next phase, the completiouzof which is shown in Figure 3, the slot 40 is fully opened, and the cove lip door has beenvdetlected Yupwardly to assist in leading the air flow over the lower wing skin 'i into that slot, and the latch hook 5 has beenY rotated from its unlatched position, as in Figures l and 2, to

Vits ready-to-latch position, as in Figure 3. Immediately thereafter the covelip door is supported solely through uptilted spoiler produces a torque countering the torque about a local center of rotation, such asis caused by the downward deflection ofthe flap. All this movement has been caused by the flap actuator, namely, the lead screw 44 and the nut 43, and no separate actuator for, the spoiler nor for the cove lip door is required.

Upon return of the ap to its up position the corresponding operations occur in reverse order. Itis believed that it will be obvious how and when theyk occur, and j.

that detaileddescription thereof is not necessary. In ythe tirst phase of the return movement, the spoilerractuator is returned to its normal position, and the spoiler door is permitted to drop down. The cam follower 34 reenters the open mouth 46d of the cam'track 46, and that cam trackvpushes aside the hook 5, back towards its unlatched position,y the final movement thereof 4being effected by the snapping of the spring 51 past its center position,as

the free end of the cam track 46 reaches a position about as in Figure 2. The cove lip door is controlled again by the cam track 46, and when the parts reach again the position of Figure l, all parts have been restored, again by operation of the flap actuator alone, to their normal positions, that is, to the positions they would occupy during normal flight.

I claim as my invention:

l. In combination with an airplane wing the trailing edge contour whereof is indented to define a rearwardly open cove intermediate its upper and lower skin contours, a slotted flap the nose whereof is receivable within such cove, means guiding and supporting said flap for movement between its up position, wherein its nose is received within said cove, and it constitutes a general continuation of the wings contour, and a down position displaced rearwardly and deflected downwardly from its up position, an actuator to shift the ap between the up and down positions, a spoiler door hingedly mounted by its forward edge upon the wing, in rearward continuation of the wings upper skin, and defining the upper boundary of said cove a cove lip door hingedly mounted by its forward edge upon the wing, in rearward continuation of the wings lower skin, and defining the lower boundary of said cove, said doors being of a length to overlap and close the exit and the entrance, respectively, of the aps slot when the flap is in its up position, but to uncover the same by rearward shifting of the iiap, means operatively connecting said ap to said doors, to tilt each door upwardly as the flap shifts rearwardly and downwardly, to define in the iiaps full down position a slot directed generally upwardly and rearwardly over the nose of the flap, and intermediate such nose and the doors, the uptilted spoiler door constituting a spoiler for airow over the wings upper skin.

2. In combination with an airplane wing the trailing edge whereof is indented to dene a rearwardly opening cove located intermediate its upper and lower skin contours, a iiap consisting of nose and trailing portions rigidly interconnected but spaced apart to define a leadingedge slot, means guiding and supporting said flap for movement between an up position, wherein its nose portion is projected within the cove and its slot is closed by the wing skin contours, and a down position, wherein it is displaced rearwardly and deflected downwardly, with its slot located externally of the cove, a cove lip door hingedly mounted by its forward edge upon the wings lower skin, and constituting the lower boundary of the cove and the trailing portion of the wings lower skin contour, and being of a length such, in relation to the amount of rearward displacement of the ilap into its down position, as to uncover the flaps slot and nose portion when the ap is in such down position, and means operatively interconnecting the flap and said cove lip door to tilt the latter upwardly as the flap approaches its down position, to dene in the aps full down position a further slot between the wings upper cove-delining skin contour and the nose portion of the ap.

3. The combination of claim 2, including complementally engageable latching elements one on the cove lip door and another support from the wing and xedly located thereabove, and means carried by the ap and engageable with said latching elements to move them into engagement to hold the door uptilted as the flap moves further towards down position, and vice versa.

4. The combination of claim 2, including a spoiler door hingedly mounted by its forward edge upon the wings upper skin, and in the region of the cove constituting the wings upper skin contour, and being of a length such, in relation to the amount of rearward displacement of the ap into its down position, as to uncover the aps slot when the flap is in such down position, and means operatively engageable between the ap and the spoiler door to tilt the latter upwardly as the flap approaches its down position, to deine the upper 6 surface of the further iiapl between tself and the nose portion ofthe'ap.

S. The combination of claim 1, including a movable latch supported from the wing and located above the swinging edge of the cove lip door, a complemental latching element' carried by the cove lip door in position for engagement by said movable latch when the door is uptilted, a latching dog operatively connected to the spoiler door, and a trip element carried by the flap, and engageable with said latch as the flap moves towards down position, to move the latch into engaging position, said trip element Abeing located to engage said latching dog when the iiap reaches full down position, to retain the spoiler door in uptilted position.

6. The combination of claim 2, including a movable latch supported upon the wing structure within the cove, and located in an unlatched position above the swinging edge ofthe cove lip door when said door is in its down position, a complemental latching element carried by the cove lip door in position for engagement Iby said latch when the door is uptilted, a trip element carried by the flap, and cngageable with said latch to move the latter into latching engagement with said complemental latching element as the flap moves towards down position, to move the latch into engaging position, and means carried by the flap and engageable with said latch as the flap moves towards its up position, to shift the latch towards its unlatched position.

7. The combination of claim 6, including a cam track upon and projecting forwardly from the flap, within the cove, a cam follower on the cove lip door guided upon said cam track, constituting the door-tilting means, the cam track being of a length to disengage the cam followe'i prior to the ap reaching its full down position, the flap-carried latch-shifting means being positioned to engage and shift the latch into latching position prior to disengagement ofthe cam track from the cam follower, for vsubsequent latching engagement with the complemental means upon the door following further shifting of the flap towards its down position, and so to hold the door uptilted, and the door-carried cam follower in position for reengagement by the cam track during shifting of the flap towards its up position, and the apcarried latch-shifting means being also positioned to reengage the latch after such reengagement of the cam and cam track, and to return the same towards unlatched position following further shifting of the iiap towards its up position.

8. The combination of claim 6, including a cam track upon and projecting forwardly from the flap, within the cove, a cam follower on the cove lip door guided upon said cam track, constituting the door-tilting means, the latch being in the form a hook pivotally mounted within the cove to swing between latching and unlatched positions, a lug formed on said hook, a trip member carried by the flap in position to engage said lug as the iiap moves toward down position, said cam track being shaped to defer uptilting of the door during the initial rearward shifting of the ap, and to swing the door upwardly for engagement of its complemental means with said latch, following the latters movement into latching position.

9. In combination with an airplane wing the trailing edge contour whereof is interrupted, a slotted flap shaped as a whole generally to complete the trailing edge contour, means guiding and supporting said flap from the wing for movement between its up position, in general continuation of the wings contour, and a down position displaced rearwardly and deflected downwardly from its up position, an actuator to shift the iiap between the up and down positions, a spoiler door hingedly mounted by its forward edge upon the wing, in rearward continuation of the wings upper skin, and of a length to close the exit of the aps slot, when the ap is in its up position, but to uncover the same by rearward shifting of the ap from Y aeeeso such up-position, and means interengageable between the flap-andtheppoilerdoor to tilt the spoiler/door upwardly about itshingefaxis as the ap shifts Yrearwardly towards its-fulldown positiorn'to define a slot betweenthe spoiler doors trailing edge and the nose ofthe rearwardly shifted apf? iY y' r t Y t 10. Injcornbination with an airplane wing' theltrailing edge `whereof isV indented to denea rearwardly open cove loeatedintermediate its upper andlower skin contours, aslotted ii'ap, means supporting said -lap from the wing for movement Y,between an up position, wherein its Y VYnoseri's received within said coye and'itsrslot is shroudedV by the boundaries thereof, and the ilap r`constitutes a general continuation of the wings contour, and a down position displaced rearwardly and deected downwardly from itsnp. position',V with its slot uncovered, an actuator. to shift`the. tlap between the up and the down positions,a spoiler .door hingedlyY rnounted by Vits forward edge-in rearward continuationof the wings upper skin, Vand constitutingthe upper'bou'ndary'of the cove, a spoiler actu-Y wardly, for engagement with and uptilting of the spoiler door, thereby to `denne a slot between Ythe'uptilted spoiler door and the nose of the rearwardly shifted ap, and vice versa.` Y n ll.v In combination with an airplane Wing the trailing edge contour whereof is interrupted, a slotted'ap shapedl i as a whole generally to complete the trailing edge .conf` tour, means guiding Vand supporting said'ap -forvirnovementbetween its up position, in general continuation'of an actuatorito shift the ap positions; fa spoilergdoor'ihingedly'mounted by'jits forwardied'ge upon the Ywing, irl-'rearward continuationsof thetwin'gs'npperskinfa c'ov'e` lip 'doorhiugedly mounted bypits 'forward edge upon the'fwing, iin rearwardl continue ation of the wings lower skill; Said '.door/s'beingof a length to cover the exit and; the entrance, respectively, of 'the aps slot, and to idene a'cove receivingY the nose of the flap, whenthe apis in its upv positiornbut to Yuncover Ysuch exit andentrance, by rearward 'shifting of the flap, earn mechanism carried :by the cove lip :door andi by the ilap,`respectively, to tilt thev ove lip door upwardly Yby shiftingofthe flap towards; its full down position,` latch rneans interengageable betweenY the-wing and the'covelip doorrto retain the doorin its uptilted position; said latch ,meansV includingV arho'ol; Swingably mountedupon the wing to'rotatebetween a latching and an Yunla'tched position,` a lng lupon the Yilap, positioned to engage said hookito rotate it'int'olatchingposition during rearward moyernent of the ap; a spoiler aetuator,can1

' means upon the wing guiding Said spoilerractuator for the'wings contour, and a down position d isr'nlacedy rear Wardly and deected downwardly from up position,

forward and rearward movement and 'for Vuptiltingin its rearward position, resilient nieans A'holding l`said spoiler Vactuator normally inla forward positionywherein itwill be engaged and moved rearwardly bylsaidilugcfollowing rotation ofthe hook by Vsaid lug; into latchin'g position,v

the spoiler actuator being organized and arranged to tilt theV spoiler'door upwardly when the spoiler actuator is thus Ymoved rearwardly and ltilted upwardly.A

References Cited in the le ofithis-gpatent- UNrrED STATES PATENTS v 2,169,416 Griswold v. Aug. 415', 1939 2,371,976 Patgh Y Manno, 1945V V2,373,365 Westberg Apr. l0, V1345 `40pm Y ciausperet a1. Y f j v Sept. 10,1946 Y FOREIGN PATENTS .Y 9871021v Y El'ance -vl----f-a-f---r-Ar Apr' ,1951f between theV up` and down Y NETE@ PATENT @FFQE @@Rltltl Patent Noe 2,836,380 May 27, 1958 Raymond E., Pearson It is heee-by eert: ^""ed that elr'or appears in the printed specification above numbered etent requiring connection and that the said Letters should read ee @effected below.,

Column 5, line 6ly for nsupportH read I supported column 6,

line l, for "tself" read n itself m; line 533 after ufoufm" insert Signed and sealed this 9th. day of September 1958.,

(SEAL) Attest;

KARL I-Io AXLINE ROBERT C. WATSON Commissioner of Patents 

